1. Field of the Invention
The present invention relates to a protective device for a feed unit, especially for a spindle sleeve of a measuring machine, whereby the feed unit is surrounded by a jacket constituted of a multiplicity of springs, which touch the feed unit in the event of a collision and thereby produce electrical contacts, and in which the lower or bottom part of the feed unit is enclosed by a protective shield.
2. Discussion of the Prior Art
A protective unit of that type is described in the disclosure of earlier German Pat. No. P 35 26 633.3, commonly assigned to the assignee of this application. In that instance, the protective shield is of a unitary construction. During a collision, the protection shield reacts comparatively sluggishly.
In the disclosure of German Laid-Open Pat. No. 35 14 444 there is described a protective device in which the spindle sleeve is encompassed by a protective jacket. This jacket is formed by an electrically-conductive mechanical body or by a multiplicity of light barriers. A mounting device for light transmitters which is arranged at the lower or bottom portion of the spindle sleeve, is itself not integrated into the protective jacket.